| Season | Astronomical Start (approx.) | End Date (approx.) | Months Involved | |--------|------------------------------|--------------------|------------------| | Spring | March Equinox (Mar 19-21) | June Solstice (Jun 20-21) | March, April, May, June | | Summer | June Solstice (Jun 20-21) | September Equinox (Sep 22-23) | June, July, August, September | | Autumn | September Equinox (Sep 22-23) | December Solstice (Dec 21-22) | September, October, November, December | | Winter | December Solstice (Dec 21-22) | March Equinox (Mar 19-21) | December, January, February, March |

The meteorological system is the simpler and more practical approach for climatology, weather forecasting, and agricultural planning. It divides the year into four seasons of three full calendar months each, based on the annual temperature cycle.

This report examines the division of the calendar year into seasons, focusing on the number of months each season comprises. It identifies two primary systems: the , based on annual temperature cycles and the calendar for consistent climate record-keeping, and the astronomical season , based on the Earth’s orbit and solstices/equinoxes. While both systems result in seasons lasting approximately three months, their start and end dates differ, leading to a fixed month allocation in meteorology and variable dates in astronomy.

From the vernal equinox (March) to the summer solstice (June).

This distribution is often used in the Northern Hemisphere. In the Southern Hemisphere, the seasons are reversed due to the Earth's tilt:

The Rhythm of the Year: How Many Months per Season? Most of us grew up learning that the year is a neat package of four seasons: spring, summer, fall, and winter. But if you’ve ever felt like winter lasts for six months while spring vanishes in a blink, you might wonder how the calendar actually divides the year.

Meteorologists and climatologists find the astronomical dates a bit messy because they start on different days each year (the 20th, 21st, or 22nd). To make record-keeping easier, they group the year into four three-month blocks based on the temperature cycle: March, April, May Summer: June, July, August Fall: September, October, November Winter: December, January, February

Seasons and their corresponding months vary slightly depending on the context, such as cultural or astronomical definitions. However, a commonly accepted distribution is:

Meteorologists divide the year into four equal three-month periods based on the temperature cycle and the Gregorian calendar. This makes it easier to track seasonal statistics. : March, April, May Summer : June, July, August Autumn : September, October, November Winter : December, January, February Astronomical Seasons

: Specific agricultural activities, like tomato irrigation, may only occur for 1.5 to 2 months per season.